This invention relates to biocatalysts, to a method for their production and to a biochemical process using such biocatalysts.
The microbiological sciences have developed rapidly during the past two decades and an increasing number of commercial biochemical processes have been developed using enzymes as biocatalysts. Examples of such biochemical processes include those described in our European Patent Specifications Nos. 76606 and 179603. In such processes the biocatalysts employed have an important role.
To date enzymes used as biocatalysts have generally been used in the forms; (a) purified enzymes; (b) wet suspensions of cells containing the enzymes; and (c) immobilised whole cells containing the enzymes. All three forms however have disadvantages which restrict their commercial applicability. Purified enzymes are very useful but are expensive to produce and their utility is restricted to processes producing high-value end products. Enzymes in wet cell suspensions lose their activity quickly. When such suspensions are to be stored even for short periods it is necessary to add other materials such as anti-freeze cryo-protectants to them and to cool to temperatures below 0.degree. C. to prevent rupture of cells contained in the suspensions. With enzymes in immobilised whole cells it is difficult to maintain the full activity of the enzymes over long periods.